Growth of thick AlGaN by metalorganic‐hydride vapor phase epitaxy

Abstract

The growth of a thick AlGaN is performed on Al 2 O 3 substrate by metalorganic vapor phase epitaxyhydride vapor phase epitaxy (MOVPE-HVPE) combined system. Thin AlN or GaN layer is grown on a substrate by MOVPE growth method with the conventional manner but in a hot-wall chamber and followed by the HVPE growth of a thick AlGaN in the same chamber. For the growth of a AlGaN layer, NH 3 and aluminum-gallium chloride formed by HCl which is flown over metallic Ga mixed with Al are used as aluminum-gallium and nitrogen sources. The peak of the cathodoluminescence (CL) spectrum of the thick AlGaN is shown at the wavelength of 354 nm. This suggests that the metallic Ga mixed with Al can be used as a group III source material in the HVPE growth of the AlGaN.

Growth of thick Al Ga1−N ternary alloy by hydride vapor-phase epitaxy

“…4 shows the growth rate of the samples shown in Fig. 3 and the driving force for the Al x Ga 1Àx N deposition (DP Al +DP Ga ) calculated by thermodynamic analysis [9,10] as a function of R Al . The mass transfer coefficient (K g ) was estimated at 1.25 Â 10 5 mm/h atm.…”

“…[3,4]. To date, although the fabrication of AlGaN template [5], freestanding wafers [6] and device structure [7][8][9] was reported, there are few reports of Al x Ga 1Àx N growth by HVPE [10]. This reason is because HVPE growth of Alcontaining materials such as AlN and AlGaN has been generally thought to be difficult due to the violent reaction between the Al source (AlCl) and the quartz (SiO 2 ) reactor.…”

HVPE growth of Al Ga1−N ternary alloy using AlCl3 and GaCl

“…Although the growth of bulk AlN has been studied by many groups as described above, relatively little is known about the growth of bulk AlGaN [13,14]. AlGaN is a ternary alloy crystal composed of AlN and GaN.…”